Purple Martins are a large swallow indigenous to North America, and are cavity-nesting birds that have finished in population over the course of the 20th century. They are almost entirely dependent upon humans to provide nesting sites, particularly across eastern North America where human populations are far more dense. Martins actually thrive in proximate to humans! To make matters worse, Purple Martin populations are also threatened by European Starlings, which are also cavity-nesting birds that will aggressively overtake martin houses, sometimes by violent force. However, these wonderful birds have been subjected to numerous scientific studies, so being a bird landlord these days is quite simple!
So where to start? Well, start by putting up a Purple Martin bird house or gourd! Purple Martin housing comes in a variety of shapes, sizes, and price, so there is a house for everyone's budget and level of commitment. If you're more adventurous, and want a bigger payoff for your work, try a multi-room wooden house, mounted to a telescoping pole system. These mammoth bird houses act as condos for entire colonies of Purple Martins, but are more expensive and difficult to maintain than the smaller plastic gourds. However, they are quite aesthetically pleasing, particularly when there are dozens of birds zipping in and out!
Here are some more tips on setting up and maintaining a Purple Martin House:
- Keep the bird house away from trees. There should be no trees taller than the house & pole you've set up at least 60 feet in any direction.
- The pole should be twelve to twenty feet in height, and you'll need to use a pole guard to keep raccoons and other predators at bay.
- If you do not have a pole guard, consider a house with deeper and larger compartments that will keep the nests out of a predator's reach.
- If there are going to be trees around, try to mount the house at a height * above * the tallest tree in the surrounding area.
- You'll need at least 24 total nesting compartments to ensure the colony thrives at your location.
- Entrance holes larger than 6 "x 6" will be an open invitation for the pesky and unwanted Starling or House Sparrow.
- Use an excluder door, or crescent shaped gourd door, to keep Starlings and Sparrows from invading the nests and wreaking havoc.
- You'll note that all Purple Martin bird houses are white, and that's for good reason. The white color reflects the heat of the summer to keep the inside nests cool.